Failure of Downregulation of Survivin Following Neoadjuvant Radiochemotherapy in Rectal Cancer Is Associated with Distant Metastases and Shortened Survival

Quality of Surgical Outcome Reporting in Randomised Clinical Trials of Multimodal Rectal Cancer Treatment: A Systematic Review

INTRODUCTION

Randomised controlled trials (RCTs) continue to provide the best evidence for treatment options, but the quality of reporting in RCTs and the completeness rate of reporting of surgical outcomes and complication data vary widely. The aim of this study was to measure the quality of reporting of the surgical outcome and complication data in RCTs of rectal cancer treatment and whether this quality has changed over time.

METHODS

Eligible articles with the keywords ("rectal cancer" OR "rectal carcinoma") AND ("radiation" OR "radiotherapy") that were RCTs and published in the English, German, Polish, or Italian language were identified by reviewing all abstracts published from 1982 through 2022. Two authors independently screened and analysed all studies. The quality of the surgical outcome and complication data was assessed based on fourteen criteria, and the quality of RCTs was evaluated based on a modified Jadad scale. The primary outcome was the quality of reporting in RCTs and the completeness rate of reporting of surgical results and complication data.

RESULTS

A total of 340 articles reporting multimodal therapy outcomes for 143,576 rectal cancer patients were analysed. A total of 7 articles (2%) met all 14 reporting criteria, 13 met 13 criteria, 27 met from 11 to 12 criteria, 36 met from 9 to 10 criteria, 76 met from 7 to 8 criteria, and most articles met fewer than 7 criteria (mean 5.5 criteria). Commonly underreported criteria included complication severity (15% of articles), macroscopic integrity of mesorectal excision (17% of articles), length of stay (18% of articles), number of lymph nodes (21% of articles), distance between the tumour and circumferential resection margin (CRM) (26% of articles), surgical radicality according to the site of the primary tumour (R0 vs. R1 + R2) (29% of articles), and CRM status (38% of articles).

CONCLUSION

Inconsistent surgical outcome and complication data reporting in multimodal rectal cancer treatment RCTs is standard. Standardised reporting of clinical and oncological outcomes should be established to facilitate comparing studies and results of related research topics.

Advances in nanotechnology-based platforms for survivin-targeted drug discovery

INTRODUCTION

Due to its unique functional impact on multiple cancer cell circuits including proliferation, apoptosis, tumor dissemination, DNA damage repair and immune response, the inhibitor of apoptosis protein (IAP) survivin has gained high interest as a molecular target and a multitude of therapeutics were developed to interfere with survivin expression and functionality. First clinical evaluations of these therapeutics, however, were disappointing highlighting the need to develop advanced delivery systems of survivin-targeting molecules to increase stability, bioavailability as well as the selective guidance to tumor tissue.

AREAS COVERED

: This review focuses on advancements in nanocarriers to molecularly target survivin in human malignancies. A plethora of nanoparticle platforms, including liposomes, polymeric systems, dendrimers, inorganic nanocarriers, RNA/DNA nanotechnology and exosomes are discussed in the background of survivin-tailored RNA interference, small molecule inhibitors, dominant negative mutants or survivin vaccination or combined modality treatment with chemotherapeutic drugs and photo- dynamic/photothermal strategies.

EXPERT OPINION

Novel therapeutic approaches include the use of biocompatible nanoformulations carrying gene silencing or drug molecules to directly or indirectly target proteins, allow for a more precise and controlled delivery of survivin therapeutics. Moreover, surface modification of these nanocarriers may result in a tumor entity specific delivery. Therefore, nanomedicine exploiting survivin-tailored strategies in a multimodal background is considered the way forwaerd to enhance the development of future personalized medicine.

Evaluation of potential tumor markers that may predict neoadjuvant treatment efficiency in rectal cancer

Objectives

The recurrence of rectal cancer or its resistance to neoadjuvant treatment develops due to the adaptation to hypoxia, apoptosis or autophagy. Survivin, one of the inhibitors of apoptosis; Beclin 1, which is a positive regulator in the autophagy pathway; and hypoxia-inducible factor-1α (HIF-1α) and carbonic anhydrase-9 (CA9), which are associated with tumor tissue hypoxia, may be related to resistance to treatment. Our aim was to evaluate the potential tumor markers that may help to monitor the response to neoadjuvant treatment in locally advanced rectal cancer (RC).

Methods

Twenty-five patients with locally advanced RC were included in the study. Gene expression and protein levels of Beclin 1, Survivin, HIF-1α, and CA9 were analyzed in fresh tissue specimens and blood samples. The relationships of these markers to tumor staging and regression grade were evaluated.

Results

Higher blood CA9 gene expression levels and lower blood HIF-1α protein levels were found in the response group according to tumor regression grade. After neoadjuvant treatment, tissue Beclin 1 and blood Survivin gene expressions and tissue CA9, blood Beclin 1 and blood HIF-1α protein levels decreased significantly.

Conclusion

Beclin 1, Survivin, HIF-1α ve CA9 may help to predict the effects of the applied treatment approach.

miR-101-3p sensitizes lung adenocarcinoma cells to irradiation via targeting BIRC5

Lung adenocarcinoma (LUAD) has been considered as the most common cause of cancer-associated mortality. Radiotherapy resistance is one of the main reasons for LUAD treatment failure. The microRNA (miR)-101-3p has been previously reported to function as a tumor suppressor in several types of cancer, including LUAD. The present study aimed to explore the role and mechanism of miR-101-3p on radioresistance of lung adenocarcinoma cells through bioinformatics analysis and biological experiments. Based on the analysis of Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) data, it was demonstrated that the expression of miR-101-3p was low in LUAD tissues compared with normal lung tissues and was associated with poor prognosis of patients with LUAD. The results of the CCK-8 assay, colony formation assay, immunofluorescence staining, caspase-3 activity assay and western blotting demonstrated that miR-101-3p overexpression sensitized LUAD cells to ionizing radiation by decreasing the abilities of LUAD cell proliferation, colony formation, DNA damage repair and increasing caspase-3 activity and apoptosis of LUAD cells following ionizing radiation. Furthermore, according to bioinformatics analysis and luciferase assay, baculoviral IAP repeat containing 5 (BIRC5) was identified as a direct target of miR-101-3p. Increased BIRC5 expression reversed the miR-101-3p-mediated increase in LUAD cell radiotherapy sensitivity. Taken together, the results of the present study demonstrated that miR-101-3p may be considered as a potential target that can enhance LUAD cell sensitivity to radiotherapy, which may provide a new strategy to improve therapy in patients with LUAD.

Tumor Suppressor Protein p53 and Inhibitor of Apoptosis Proteins in Colorectal Cancer-A Promising Signaling Network for Therapeutic Interventions

Simple Summary

Tumor suppressor 53 (p53) is a multifunctional protein that regulates cell cycle, DNA repair, apoptosis and metabolic pathways. In colorectal cancer (CRC), mutations of the gene occur in 60% of patients and are associated with a more aggressive tumor phenotype and resistance to anti-cancer therapy. In addition, inhibitor of apoptosis (IAP) proteins are distinguished biomarkers overexpressed in CRC that impact on a diverse set of signaling pathways associated with the regulation of apoptosis/autophagy, cell migration, cell cycle and DNA damage response. As these mechanisms are further firmly controlled by p53, a transcriptional and post-translational regulation of IAPs by p53 is expected to occur in cancer cells. Here, we aim to review the molecular regulatory mechanisms between IAPs and p53 and discuss the therapeutic potential of targeting their interrelationship by multimodal treatment options.

Abstract

Despite recent advances in the treatment of colorectal cancer (CRC), patient’s individual response and clinical follow-up vary considerably with tumor intrinsic factors to contribute to an enhanced malignancy and therapy resistance. Among these markers, upregulation of members of the inhibitor of apoptosis protein (IAP) family effects on tumorigenesis and radiation- and chemo-resistance by multiple pathways, covering a hampered induction of apoptosis/autophagy, regulation of cell cycle progression and DNA damage response. These mechanisms are tightly controlled by the tumor suppressor p53 and thus transcriptional and post-translational regulation of IAPs by p53 is expected to occur in malignant cells. By this, cellular IAP1/2, X-linked IAP, Survivin, BRUCE and LIVIN expression/activity, as well as their intracellular localization is controlled by p53 in a direct or indirect manner via modulating a multitude of mechanisms. These cover, among others, transcriptional repression and the signal transducer and activator of transcription (STAT)3 pathway. In addition, p53 mutations contribute to deregulated IAP expression and resistance to therapy. This review aims at highlighting the mechanistic and clinical importance of IAP regulation by p53 in CRC and describing potential therapeutic strategies based on this interrelationship.

Identification of TRIM25 as a Negative Regulator of Caspase-2 Expression Reveals a Novel Target for Sensitizing Colon Carcinoma Cells to Intrinsic Apoptosis

Colorectal cancer (CRC) is one of the most common cancers that is characterized by a high mortality due to the strong metastatic potential of the primary tumor and the high rate of therapy resistance. Hereby, evasion of apoptosis is the primary underlying cause of reduced sensitivity of tumor cells to chemo- and radiotherapy. Using RNA affinity chromatography, we identified the tripartite motif-containing protein 25 (TRIM25) as a bona fide caspase-2 mRNA-binding protein in colon carcinoma cells. Loss-of-function and gain-of-function approaches revealed that TRIM25 attenuates the protein levels of caspase-2 without significantly affecting caspase-2 mRNA levels. In addition, experiments with cycloheximide revealed that TRIM25 does not affect the protein stability of caspase-2. Furthermore, silencing of TRIM25 induced a significant redistribution of caspase-2 transcripts from RNP particles to translational active polysomes, indicating that TRIM25 negatively interferes with caspase-2 translation. Functionally, the elevation in caspase-2 upon TRIM25 depletion significantly increased the sensitivity of colorectal cells to drug-induced intrinsic apoptosis as implicated by increased caspase-3 cleavage and cytochrome c release. Importantly, the apoptosis-sensitizing effects by transient TRIM25 knockdown were rescued by concomitant silencing of caspase-2, demonstrating a critical role of caspase-2. Inhibition of caspase-2 by TRIM25 implies a survival mechanism that critically contributes to chemotherapeutic drug resistance in CRC.

Ovarian Primary and Metastatic Tumors Suppressed by Survivin Knockout or a Novel Survivin Inhibitor

Survivin, a member of the inhibitor of apoptosis family, is upregulated in multiple cancers including ovarian cancer, but is rarely detectable in normal tissues. We previously reported that survivin promoted epithelial-to-mesenchymal transition (EMT) in ovarian cancer cells, suggesting that survivin may contribute to ovarian tumor metastasis and chemoresistance. In this study, we tested whether knockout or pharmacologic inhibition of survivin overcomes chemoresistance and suppresses tumor metastasis. The genetic loss of survivin suppressed tumor metastasis in an orthotopic ovarian cancer mouse model. To pharmacologically test the role of survivin on ovarian tumor metastasis, we treated chemo-resistant ovarian cancer cells with a selective survivin inhibitor, MX106, and found that MX106 effectively overcame chemoresistance in vitro MX106 inhibited cell migration and invasion by attenuating the TGFβ pathway and inhibiting EMT in ovarian cancer cells. To evaluate the efficacy of MX106 in inhibiting ovarian tumor metastasis, we treated an orthotopic ovarian cancer mouse model with MX106, and found that MX106 efficiently inhibited primary tumor growth in ovaries and metastasis in multiple peritoneal organs as compared with vehicle-treated control mice. Our data demonstrate that inhibition of survivin using either genetic knockout or a novel inhibitor MX106 suppresses primary ovarian tumor growth and metastasis, supporting that targeting survivin could be an effective therapeutic approach in ovarian cancer.

Next-Generation Sequencing May Discriminate Extreme Long-term versus Short-term Survival in Patients with Metastatic Small Cell Lung Cancer (SCLC)

BACKGROUND: Molecular underpinnings that may prognosticate survival could increase understanding of small cell lung cancer (SCLC) tumor behavior. Here, we report the clinicopathological characteristics and biomarker profiles of short-term (ST) versus long-term (LT) survival in patients with metastatic SCLC. METHODS: Of the 876 consecutive metastatic SCLC patients receiving standard of care therapy, 44 met the definition of LT and 91 for ST, respectively. Available FFPE tumor tissue blocks were analyzed by next-generation sequencing (NGS). Analysis included gene mutations, copy number variations, mRNA expression, and protein expression by immunohistochemistry, followed by correlation with clinicopathological characteristics. RESULTS: There were no statistically significant and clinically relevant differences in cases with or without FFPE according to major clinicopathological variables in ST and LT. However, according to NGS, five mutually exclusive gene mutations were identified (E1A binding protein P300 [EP300] p.N217S; p.E152K; human epidermal growth factor receptor 4 [ERBB4] p.E317K; BRCA1, DNA repair associated [BRCA1] p.E1661N, and epidermal growth factor receptor [EGFR] p.V742A). Comparing LT vs. ST survivals, a twofold increase was found in the average predicted number of drugs per patient off compendium. We found high SSTR2 mRNA expressions in all LT patients (vs. two [20%] ST patients), which may reflect more benign neuroendocrine tumor characteristics. CONCLUSIONS: Consolidation radiation therapy and higher predicted drug sensitivity for off compendium were associated with LT compared to ST patients in SCLC. NGS profiling of extreme survivals may improve classification of SCLC and possibly identify clinically relevant new targets.

Phospho-ERK levels as predictors for chemotherapy of rectal carcinoma

Treatment of rectal cancer has been vastly improved by advances in surgery and radiochemotherapy but remains an important cause of morbidity and mortality worldwide. A particular problem is the lack of predictive markers that can help to individualize treatment. The growth- and apoptosis-regulating signaling molecules ERK 1 and 2 are important to cancer growth and progression. They are activated through phosphorylation, which is initiated by a cascade involving the EGF receptor and RAS as upstream regulators. Moreover, in vitro studies indicate that phospho-ERKs interfere with 5-fluorouracil-based chemotherapy. Recently, we showed that high levels of phospho-ERKs in rectal cancer cells predict poor responses to neoadjuvant (preoperative) radiochemotherapy. We now report that preoperative phospho-ERK levels also can subdivide high-risk rectal cancer patients into a favorable and a poor prognostic group with respect to recurrence-free survival. Importantly, phospho-ERK levels were of predictive significance only in high-risk patients, who received adjuvant (postoperative) chemotherapy, but not in high-risk patients not receiving such therapy. Our results suggest that high cancer cell levels of phospho-ERK predict poor responsiveness to both preoperative and postoperative chemotherapy of rectal cancer.

A review of preoperative chemoradiotherapy for lower rectal cancer

In Western countries, rectal cancer has been treated by chemoradiotherapy (CRT) for several decades now, and good local control has been reported. However, Japanese guidelines did not strongly recommend CRT, because CRT is only useful for achieving local control and imbues no survival benefit. For this reason, CRT was rarely used to treat rectal cancer in Japan. However, in the 2000s, several studies involving CRT began to be reported from Western countries, such as “correlation between pathological complete response and survival,” “induction chemotherapy followed by CRT,” and “watch-and-wait policies.” These studies were directly correlated with survival of and benefits to the patients. Given these findings, Japanese institutions have recently begun to introduce CRT for rectal cancer. Therefore, in the present study, we reviewed several topics regarding CRT for rectal cancer.

Honokiol Radiosensitizes Squamous Cell Carcinoma of the Head and Neck by Downregulation of Survivin

Purpose: Previous studies revealed diverging results regarding the role of survivin in squamous cell carcinoma of the head and neck (SCCHN). This study aimed to evaluate the clinical significance of survivin expression in SCCHN; the function of survivin in DNA-damage repair following ionizing radiation therapy (RT) in SCCHN cells; and the potential of honokiol to enhance RT through downregulation of survivin.Experimental Design: Expression of survivin in SCCHN patient primary tumor tissues (n = 100) was analyzed and correlated with clinical parameters. SCCHN cell lines were used to evaluate the function of survivin and the effects of honokiol on survivin expression in vitro and in vivoResults: Overexpression of survivin was significantly associated with lymph nodes' metastatic status (P = 0.025), worse overall survival (OS), and disease-free survival (DFS) in patients receiving RT (n = 65, OS: P = 0.024, DFS: P = 0.006) and in all patients with SCCHN (n = 100, OS: P = 0.002, DFS: P = 0.003). In SCCHN cells, depletion of survivin led to increased DNA damage and cell death following RT, whereas overexpression of survivin increased clonogenic survival. RT induced nuclear accumulation of survivin and its molecular interaction with γ-H2AX and DNA-PKCs. Survivin specifically bound to DNA DSB sites induced by I-SceI endonuclease. Honokiol (which downregulates survivin expression) in combination with RT significantly augmented cytotoxicity in SCCHN cells with acquired radioresistance and inhibited growth in SCCHN xenograft tumors.Conclusions: Survivin is a negative prognostic factor and is involved in DNA-damage repair induced by RT. Targeting survivin using honokiol in combination with RT may provide novel therapeutic opportunities. Clin Cancer Res; 24(4); 858-69. ©2017 AACR.

Organ preservation in rectal cancer - Challenges and future strategies

Neoadjuvant radiochemotherapy with subsequent total mesorectal excision is the standard of care for locally advanced rectal cancer. While this multimodal strategy has decreased local recurrences rates below 5%, long-term morbidities are considerable in terms of urinary, sexual or bowel functioning. At the same time approximately 10–20% of patients have no evidence of residual tumour in their surgical specimen. Pioneering studies from Brazil have suggested that surgery can safely be omitted in carefully selected patients with a clinical complete response after radiochemotherapy. Although confirmatory studies showed similar results, challenges in terms of optimizing radiochemotherapy for organ-preservation, appropriate selection of patients for non-operative management and the safety of this approach remain. The present review will summarize the current data on organ-preservation in rectal cancer and discuss the challenges that need to be addressed in future trials.

Phospho-ERK1/2 levels in cancer cell nuclei predict responsiveness to radiochemotherapy of rectal adenocarcinoma

Locally advanced rectal adenocarcinoma is treated with radiochemotherapy (RCT) before surgery. The response to RCT is heterogeneous and consensus regarding reliable predictors is lacking. Since the ERK pathway is implicated in radioprotection, we examined pretreatment biopsies from 52 patients by immunohistochemistry for phosphorylated ERK (pERK). Immunostaining for pERK was considerably enhanced by use of alkaline demasking. Nuclear staining occurred in both cancer cells and stromal cells. Blind-coded sections were scored by 2 independent investigators. In patients showing no residual tumor after RCT (TRG1), staining for pERK in cancer, but not stromal, cell nuclei was significantly weaker than in patients showing a poor RCT response (TRG1 vs TRG4: p = 0.0001). Nuclear staining for pERK predicted poor responders, as illustrated by receiver operating characteristic curves with an area under curve of 0.86 (p = 0.0007) and also predicted downstaging (area under curve: 0.76; p = 0.01). A number of controls documented the specificity of the optimized staining method and results were confirmed with another pERK antibody. Thus, staining for pERK in cancer cell nuclei can predict the response to RCT and may help spare poor responders this treatment. These results also raise the question whether inhibitors of ERK activation may serve as response modifiers of RCT.

Immunological Landscape and Clinical Management of Rectal Cancer

The clinical management of rectal cancer and colon cancer differs due to increased local relapses in rectal cancer. However, the current molecular classification does not differentiate rectal cancer and colon cancer as two different entities. In recent years, the impact of the specific immune microenvironment in cancer has attracted renewed interest and is currently recognized as one of the major determinants of clinical progression in a wide range of tumors. In colorectal cancer, the density of lymphocytic infiltration is associated with better overall survival. Due to the need for biomarkers of response to conventional treatment with chemoradiotherapy in rectal tumors, the immune status of rectal cancer emerges as a useful tool to improve the management of patients.

The SMAC mimetic BV6 sensitizes colorectal cancer cells to ionizing radiation by interfering with DNA repair processes and enhancing apoptosis

Background

In the present study, we aimed to investigate the effect of counteracting inhibitor of apoptosis (IAP) proteins using the small molecule Second Mitochondria-derived Activator of Caspase (SMAC) mimetic BV6 in combination with ionizing radiation on apoptosis, cell cycle regulation, DNA double-strand break (DSB) repair, three-dimensional (3D) clonogenic survival and expression of IAPs in colorectal carcinoma cells.

Material and methods

Colorectal cancer cell lines (HCT-15, HT-29, SW480) were subjected to BV6 treatment (0–4 μM) with or without irradiation (2–8 Gy, single dose) followed by MTT, Caspase 3/7 activity, γH2AX/53BP1 foci assays, AnnexinV staining, cell cycle analysis, 3D colony forming assays and Western blotting (cellular IAP1 (cIAP1) and cIAP2, Survivin, X-linked IAP (XIAP)).

Results

BV6 treatment decreased cell viability and significantly increased irradiation-induced apoptosis as analyzed by Caspase 3/7 activity, AnnexinV-positive and subG1 phase cells. While basal 3D clonogenic survival was decreased in a cell line-dependent manner, BV6 significantly enhanced cellular radiosensitivity of all cell lines in a concentration-dependent manner and increased the number of radiation-induced γH2AX/53BP1-positive foci. Western blot analysis revealed a markedly reduced cIAP1 expression at 4 h after BV6 treatment in all cell lines, a substantial reduction of XIAP expression in SW480 and HT-29 cells at 24 h and a slightly decreased cIAP2 expression in HCT-15 cells at 48 h after treatment. Moreover, single or double knockdown of cIAP1 and XIAP resulted in significantly increased residual γH2AX/53BP1-positive foci 24 h after 2 Gy and radiosensitization relative to control small interfering RNA (siRNA)-treated cells.

Conclusion

The SMAC mimetic BV6 induced apoptosis and hampered DNA damage repair to radiosensitize 3D grown colorectal cancer cells. Our results demonstrate IAP targeting as a promising strategy to counteract radiation resistance of colorectal cancer cells.

Electronic supplementary material

The online version of this article (doi:10.1186/s13014-015-0507-4) contains supplementary material, which is available to authorized users.

Targeted silencing of inhibitors of apoptosis proteins with siRNAs: a potential anti-cancer strategy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies, with a very poor prognosis. Despite significant improvements in diagnosis and treatment in recent years, the long-term therapeutic efficacy is poor, partially due to tumor metastasis, recurrence, and resistance to chemo- or radio-therapy. Recently, it was found that a major feature of tumors is a combination of unrestrained cell proliferation and impaired apoptosis. There are now 8 recognized members of the IAP-family: NAIP, c-IAP1, c-IAP2, XIAP, Survivin, Bruce, Livin and ILP-2. These proteins all contribute to inhibition of apoptosis, and provide new potential avenues of cancer treatment. As a powerful tool to suppress gene expression in mammalian cells, RNAi species for inhibiting IAP genes can be directed against cancers. This review will provide a brief introduction to recent developments of the application IAP-siRNA in tumor studies, with the aim of inspiring future treatment of HCC.

Upregulation of stromal cell-derived factor 1α expression is associated with the resistance to neoadjuvant chemoradiotherapy of locally advanced rectal cancer: angiogenic markers of neoadjuvant chemoradiation

The ability to achieve pathologic downstaging after neoadjuvant chemoradiotherapy (NCRT) is correlated with improved survival in locally advanced rectal cancer (LARC). However, there is no effective predictive markers. In this study, the expression of angiogenic markers was evaluated in pre-treatment biopsies and corresponding post-treatment resection specimens, and were correlated to histopathological tumour characteristics and response. Fifty-five patients with stage II/III rectal cancer treated with 5-fluorouracil (5-FU)-based NCRT were studied. All patients were administered NCRT followed by surgical resection. Immunohistochemical staining for angiogenic markers [hypoxia-inducible factor 1α (HIF‑1α), vascular endothelial growth factor (VEGF), stromal cell‑derived factor 1α (SDF-1α) and placental growth factor (PlGF)] was performed on specimens obtained before NCRT and after surgery. Expression of VEGF, PlGF and HIF-1α protein was downregulated after NCRT in the rectal cancer tissues (P<0.001, P=0.001 and P=0.044, respectively). However, SDF-1α was upregulated after NCRT (P<0.001). Moreover, upregulated expression of SDF-1α (P=0.016) and positive PlGF staining (P=0.001) after NCRT were significantly associated with resistance to NCRT. On multivariate analysis, positive PlGF staining after NCRT was found to be independently associated with resistance to NCRT (P=0.013). Our data suggest that SDF-1α and PlGF should be evaluated as new targets for NCRT in LARC.

Tumor Regression Grading After Preoperative Chemoradiotherapy for Locally Advanced Rectal Carcinoma Revisited: Updated Results of the CAO/ARO/AIO-94 Trial

Purpose

We previously described the prognostic impact of tumor regression grading (TRG) on the outcome of patients with rectal carcinoma treated with preoperative chemoradiotherapy (CRT) in the CAO/ARO/AIO-94 trial. Here we report long-term results after a median follow-up of 132 months.

Patients and Methods

TRG after preoperative CRT was determined in 386 surgical specimens by the amount of viable tumor cells versus fibrosis, ranging from TRG 4 (no viable tumor cells) to TRG 0 (no signs of regression). Clinicopathologic parameters and TRG were correlated to the cumulative incidence of local recurrence, distant metastasis, and disease-free survival (DFS).

Results

Ten-year cumulative incidence of distant metastasis and DFS were 10.5% and 89.5% for patients with TRG 4 (complete regression), 29.3% and 73.6% for TRG 2 and 3 (intermediate regression), and 39.6% and 63% for TRG 0 and 1 (poor regression), respectively (P = .005 and P = .008, respectively). On multivariable analysis, residual lymph node metastasis (ypN+) and TRG were the only independent prognostic factors for cumulative incidence of distant metastasis (P < .001 and P = .035, respectively) and DFS (P < .001 and P = .039, respectively), whereas local recurrence was significantly affected by ypN status (P < .001) and lymphatic invasion (P = .026).

Conclusion

Complete and intermediate tumor regressions were associated with improved long-term outcome in patients with rectal carcinoma after preoperative CRT independent of clinicopathologic parameters. This classification system needs to be prospectively tested in multiple data sets to validate its reproducibility in a wider setting.

Clinical prognostic value of combined analysis of Aldh1, Survivin, and EpCAM expression in colorectal cancer

BACKGROUND

Tumour aggressiveness might be related to the degree of main cancer hallmark acquirement of tumour cells, reflected by expression levels of specific biomarkers. We investigated the expression of Aldh1, Survivin, and EpCAM, together reflecting main cancer hallmarks, in relation to clinical outcome of colorectal cancer (CRC) patients.

METHODS

Immunohistochemistry was performed using a tumour tissue microarray of TNM (Tumour, Node, Metastasis)-stage I-IV CRC tissues. Single-marker expression or their combination was assessed for associations with the clinical outcome of CRC patients (N=309).

RESULTS

Increased expression of Aldh1 or Survivin, or decreased expression of EpCAM was each associated with poor clinical outcome, and was therefore identified as clinically unfavourable expression. Analyses of the combination of all three markers showed worse clinical outcome, specifically in colon cancer patients, with an increasing number of markers showing unfavourable expression. Hazard ratios ranged up to 8.3 for overall survival (P<0.001), 36.6 for disease-specific survival (P<0.001), and 27.1 for distant recurrence-free survival (P<0.001).

CONCLUSIONS

Our data identified combined expression levels of Aldh1, Survivin, and EpCAM as strong independent prognostic factors, with high hazard ratios, for survival and tumour recurrence in colon cancer patients, and therefore reflect tumour aggressiveness.

The prognostic value of survivin expression in patients with colorectal carcinoma: a meta-analysis

OBJECTIVE

The prognostic role of survivin in colorectal carcinoma remains controversial. This meta-analysis aimed to explore the association between survivin expression and survival outcomes in patients with colorectal carcinoma.

METHODS

A comprehensive literature search for relevant studies published up to April 2013 was performed using PubMed, MEDLINE and ISI Web of Science. Only articles in which survivin was detected by immunohistochemical staining were included. This meta-analysis was done using STATA and Review Manager.

RESULTS

A total of 1784 patients from 14 studies were included in the analysis. Our results showed that survivin overexpression in patients with colorectal carcinoma was significantly associated with poor overall survival (hazard ratio, 1.505; 95% confidence interval, 1.197-1.893; P = 0.000) and disease-free survival (hazard ratio, 2.323; 95% confidence interval, 1.687-3.199; P = 0.000). The results indicated that a significant relationship between survivin expression and overall survival was also exhibited in studies with an Asian country (hazard ratio, 1.684; 95% confidence interval, 1.477-1.921), patient number >100 (hazard ratio, 1.604; 95% confidence interval, 1.371-1.877), the cut-off level <50% (hazard ratio, 1.449; 95% confidence interval, 1.045-2.010), the percentage of survivin overexpression >50% (hazard ratio, 1.528; 95% confidence interval, 1.056-2.211) and the hazard ratio estimated (hazard ratio, 1.643; 95% confidence interval, 1.262-2.139). Moreover, upregulation of survivin was associated with stages (III/IV vs. I/II: odds ratio, 1.08; 95% confidence interval, 0.80-1.46), the depth of invasion (T3/T4 vs. T1/T2: odds ratio, 1.79; 95% confidence interval 0.67-4.74), lymph node metastasis (positive vs. negative: odds ratio, 1.49; 95% confidence interval, 0.99-2.26), distant metastasis (positive vs. negative: odds ratio, 2.37; 95% confidence interval, 0.99-5.72) and grade of differentiation (well/moderate vs. poor: odds ratio, 1.02; 95% confidence interval, 0.43-2.41), but without significance.

CONCLUSION

The present meta-analysis indicated that upregulation of survivin was associated with poor prognosis in patients with colorectal carcinoma.

The prognostic value of the apoptosis pathway in colorectal cancer: a review of the literature on biomarkers identified by immunohistochemistry

Research towards biomarkers that predict patient outcome in colorectal cancer (CRC) is rapidly expanding. However, none of these biomarkers have been recommended by the American Association of Clinical Oncology or the European Group on Tumor Markers. Current staging criteria result in substantial under-and over-treatment of CRC patients. Evasion of apoptosis, a characteristic feature of tumorigenesis, is known to correlate with patient outcome. We reviewed the literature on immunohistochemistry-based studies between 1998 and 2011 describing biomarkers in this pathway in CRC and identified 26 markers. Most frequently described were p53, Bcl-2, survivin, and the Fas and TRAILR1 receptors and their ligands. None of the studies reviewed provided sufficient support for implementing a single marker into current clinical practice. This is likely due to the complex biology of this pathway. We suggest focusing on the combination of key markers within the apoptosis pathway that together represent an ‘apoptotic tumor profile’, which better reflects the status of this pathway in a tumor.

Double targeting of Survivin and XIAP radiosensitizes 3D grown human colorectal tumor cells and decreases migration

BACKGROUND AND PURPOSE

In the present study, we aimed to investigate the effect of single and double knockdown of the inhibitor of apoptosis proteins (IAP) Survivin and X-linked IAP (XIAP) on three-dimensional (3D) clonogenic survival, migration capacity and underlying signaling pathways.

MATERIALS AND METHODS

Colorectal cancer cell lines (HCT-15, SW48, SW480, SW620) were subjected to siRNA-mediated single or Survivin/XIAP double knockdown followed by 3D colony forming assays, cell cycle analysis, Caspase activity assays, migration assays, matrigel transmigration assays and Western blotting (Survivin, XIAP, Focal adhesion kinase (FAK), p-FAK Y397, Akt1, p-Akt1 S473, Extracellular signal-regulated kinase (ERK1/2), p-ERK1/2 T202/Y204, Glycogen synthase kinase (GSK)3β, p-GSK3β S9, nuclear factor (NF)-κB p65).

RESULTS

While basal cell survival was altered cell line-dependently, Survivin or XIAP single and Survivin/XIAP double knockdown enhanced cellular radiosensitivity of all tested cancer cell lines grown in 3D. Particularly double knockdown conditions revealed accumulation of cells in G2/M, increased subG1 fraction, elevated Caspase 3/7 activity, and reduced migration. Intracellular signaling showed dephosphorylation of FAK and Akt1 upon Survivin and/or Survivin/XIAP silencing.

CONCLUSIONS

Our results strengthen the notion of Survivin and XIAP to act as radiation resistance factors and further indicate that these apoptosis-regulating proteins are also functioning in cell cycling and cell migration.

Survivin, Ki-67 and tumor grade as predictors of response to docetaxel-based neoadjuvant chemotherapy in locally advanced breast cancer

The response rates to neoadjuvant chemotherapy (NAC) in patients with locally advanced breast cancer (LABC) may vary and the risks may outweigh the benefits in poorly selected patients. This study investigated whether survivin expression, high-level Ki-67 expression, estrogen-receptor (ER) tumor status and high tumor grade are able to predict response to docetaxel-based NAC in LABC patients, in order to perform breast-conserving surgery. In this study, 68 patients (IIb-IIIb) completed 4–6 cycles of TAC (75 mg/m² docetaxel, 60 mg/m² pirarubicin and 500 mg/m² cyclophosphamide, administered every 3 weeks). Tumor samples were obtained prior to chemotherapy. The response to chemotherapy was quantified clinically and pathologically and the histological and molecular tumor characteristics were determined. Association with response was assessed for all the parameters and the patients underwent breast-conserving surgery or radical mastectomy accordingly. A clinical complete response was observed in 21 (31%) and a partial response in 37 (54%) of the 68 patients. Thus, the overall clinical response rate (ORR) was 85%. A pathological complete response (pCR) was observed in 14 (20%) of the 68 patients and 37 patients (54%) underwent breast-conserving surgery. In the univariate analysis, survivin expression, high-level Ki-67 expression and high tumor grade (grade III) were significantly associated with ORR (P=0.007, 0.024 and 0.047, respectively). Survivin expression and high-level Ki-67 expression were significantly associated with pCR (P=0.029 and 0.048, respectively). In the multivariate analysis, survivin expression (P=0.030) and tumor grade (P=0.036), but not high-level Ki-67 and ER expression, were significantly associated with ORR and none of these factors was significantly associated with pCR. In conclusion, expression of survivin and high tumor grade were of predictive value for ORR to docetaxel-based NAC in LABC patients, leading to more patients successfully undergoing breast conserving-surgery. Immunohistochemistry of survivin and the Elston and Ellis criteria of tumor grade may provide a widely applicable, cost-effective method of patient selection for NAC.

[Molecular signaling pathways. Mechanisms and clinical use]

This brief summary on the role of experimental radiation oncology highlights several new research topics and research approaches that offer great potential for the optimization of modern radiation oncology. In addition, many areas of research, such as hypoxia, angiogenesis, the immune system, and metabolism, to name a few, comprise a substantial part of our current knowledge of tumor and radiation biology. Which new insights and therapeutic possibilities via the Human Cancer Genome Project or new processes, such as next generation sequencing may offer, cannot be easily foreseen at present. However, we do know for certain: radiation biology has and will continue to contribute to improvements in radiation oncology.

Survivin, a target to modulate the radiosensitivity of Ewing's sarcoma

BACKGROUND AND PURPOSE

Radiotherapy constitutes an essential element in the multimodal therapy of Ewing's sarcoma. Compared to other sarcomas, Ewing tumors normally show a good response to radiotherapy. However, there are consistently tumors with a radioresistant phenotype, and the underlying mechanisms are not known in detail. Here we investigated the association between survivin protein expression and the radiosensitivity of Ewing's sarcoma in vitro.

MATERIAL AND METHODS

An siRNA-based knockdown approach was used to investigate the influence of survivin expression on cell proliferation, double-strand break (DSB) induction and repair, apoptosis and colony-forming ability in four Ewing's sarcoma cell lines with and without irradiation.

RESULTS

Survivin protein and mRNA were upregulated in all cell lines tested in a dose-dependent manner. As a result of survivin knockdown, STA-ET-1 cells showed reduced cell proliferation, an increased number of radiation-induced DSBs, and reduced repair. Apoptosis was increased by knockdown alone and increased further in combination with irradiation. Colony formation was significantly reduced by survivin knockdown in combination with irradiation.

CONCLUSION

Survivin is a radiation-inducible protein in Ewing's sarcoma and its down-regulation sensitizes cells toward irradiation. Survivin knockdown in combination with radiation inhibits cell proliferation, repair, and colony formation significantly and increases apoptosis more than each single treatment alone. This might open new perspectives in the radiation treatment of Ewing's sarcoma.

High survivin expression as a risk factor in patients with anal carcinoma treated with concurrent chemoradiotherapy

PURPOSE

To investigate the prognostic value of survivin expression in pretreatment specimens from patients with anal cancer treated with concurrent 5-FU and mitomycin C-based chemoradiation (CRT).

MATERIAL AND METHODS

Immunohistochemical staining for survivin was performed in pretreatment biopsies of 62 patients with anal carcinoma. Survivin expression was correlated with clinical and histopathological characteristics as well as local failure free- (LFFS), distant metastases free- (DMFS), cancer specific- (CSS), and overall survival (OS).

RESULTS

Survivin staining intensity was weak in 10%, intermediate in 48% and intense in 42% of the patients. No association between survivin expression and clinicopathologic factors (tumor stage, age and HIV status) could be shown. In univariate analysis, the level of survivin staining was significantly correlated with DMFS (low survivin vs. high survivin: 94% vs. 74%, p = 0.04). T-stage, N-stage and the tumor grading were significantly associated with OS and CSS and with DMFS and LFFS, respectively. In multivariate analysis, survivin was confirmed as independent prognostic parameter for DMFS (RR, 0.04; p = 0.02) and for OS (RR, 0.27; p = 0.04).

CONCLUSION

Our results demonstrated that the level of pretreatment survivin is correlated with the clinical outcome in patients with anal carcinoma treated with concurrent CRT. Further studies are warranted to elucidate the complex role of survivin for the oncologic treatment and to exploit the protein as a therapeutic target in combined modality treatment of anal cancer.

Survivin is highly expressed in CD34(+)38(-) leukemic stem/progenitor cells and predicts poor clinical outcomes in AML

Survivin, a member of the inhibitors of apoptosis protein family, plays important roles in cell proliferation and survival and is highly expressed in various malignancies, including leukemias. To better understand its role in acute myeloid leukemia (AML), we profiled survivin expression in samples obtained from 511 newly diagnosed AML patients and in CD34(+)38(-) AML stem/progenitor cells using a validated reverse-phase protein array; we correlated its levels with clinical outcomes and with levels of other proteins in the same sample set. We found that survivin levels were higher in bone marrow than in paired peripheral blood leukemic cells (n = 140, P = .0001) and that higher survivin levels significantly predicted shorter overall (P = .016) and event-free (P = .023) survival in multivariate Cox model analysis. Importantly, survivin levels were significantly higher in CD34(+)38(-) AML stem/progenitor cells than in bulk blasts and total CD34(+) AML cells (P < .05). Survivin expression correlated with the expressions of multiple proteins involved with cell proliferation and survival. Particularly, its expression strongly correlated with HIF1α in the stem/progenitor cell compartment. These results suggest that survivin is a prognostic biomarker in AML and that survivin, which is overexpressed in AML stem/progenitor cells, remains a potentially important target for leukemia therapy.

The molecular basis of chemoradiosensitivity in rectal cancer: implications for personalized therapies

Introduction

Preoperative chemoradiotherapy represents the standard treatment for patients with locally advanced rectal cancer. Unfortunately, the response of individual tumors to multimodal treatment is not uniform and ranges from complete response to complete resistance. This poses a particular problem for patients with a priori resistant tumors because they may be exposed to irradiation and chemotherapy, treatment regimens that are both expensive and at times toxic, without benefit. Accordingly, there is a strong need to establish molecular biomarkers that predict the response of an individual patient’s tumor to multimodal treatment and that indicate treatment-associated toxicities prior to therapy. Such biomarkers may guide clinicians in choosing the best possible treatment for each individual patient. In addition, these biomarkers could be used to identify novel molecular targets and thereby assist in implementing novel strategies to sensitize a priori resistant tumors to multimodal treatment regimens.

Objective

The aim of this review is to summarize recent findings about the molecular basis of treatment resistance and treatment toxicity in patients with rectal cancer. Whole-genome, as well as single-biomarker or multibiomarker, analyses and their potential implications will be highlighted. At the end, we will outline a future vision of rectal cancer treatment in the era of personalized medicine.

Gender-specific acute organ toxicity during intensified preoperative radiochemotherapy for rectal cancer

Patients with locally advanced rectal cancer (cUICC stages II/III) are typically treated with preoperative 5-fluorouracil-based (5-FU-based) radiochemotherapy (RCT). However, trials are currently being conducted to improve the complete remission rates and the systemic control by combining 5-FU with oxaliplatin. The primary objective was to identify the subgroups of rectal cancer patients who were at risk for high-grade toxicity. All 196 patients who were included in the present study were treated with 50.4 Gy and chemotherapy that included either 5-FU (n = 115) or 5-FU+oxaliplatin (n = 81). The preoperative RCT was followed by a total mesorectal excision and adjuvant chemotherapy. Acute toxicity was monitored weekly and a toxicity grade ≥3 (Common Toxicity Criteria) for a skin reaction, cystitis, proctitis, or enteritis was defined as high-grade acute organ toxicity. After RCT with 5-FU+oxaliplatin, complete tumor remission was achieved in 13.6% of the patients and in 11.3% after RCT with 5-FU alone. Complete irradiation dosages of 50.4 Gy were given to 99% (5-FU) and 95% (5-FU+oxaliplatin) of the patients. Concomitant chemotherapy was fully administered in 95% of the patients treated with 5-FU compared with the 84% of patients treated with 5-FU+oxaliplatin. A significantly higher proportion of acute organ toxicity was found in the patients who were treated with 5-FU+oxaliplatin compared with those who were treated with 5-FU. Additionally, women with a low body mass index were at the highest risk for acute organ toxicity. These results suggest that there are basic clinical parameters, such as gender and body mass index, that may be potential markers for generating individual risk profiles of RCT-induced toxicity.